


Riddle Me This

by HuaFeiHua



Category: Shingeki no Kyojin | Attack on Titan
Genre: Alternate Universe - High School, Declarations Of Love, F/M, Love Notes, Mystery, Riddles, it was going to be armin/a mystery girl but then i decided i don't tag that way, it's the journey that matters anyway, technically. i suppose., there's like a million billion cameos courtesy other snk characters
Language: English
Status: Completed
Published: 2017-07-19
Updated: 2017-08-13
Packaged: 2018-12-04 02:50:23
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 5
Words: 8,417
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11545941
Author URL: https://archiveofourown.org/users/HuaFeiHua/pseuds/HuaFeiHua
Summary: In which Armin one day finds a mysterious, coded note on his desk asking him if he would like to go on a scavenger hunt to find the person who declared their love to him in that same note. Of course, he says yes.





	1. Chapter 1

**Author's Note:**

  * For [FullMetalGuardian](https://archiveofourown.org/users/FullMetalGuardian/gifts).

**Notes for the Chapter:**

> (a gift to fullmetalguardian because they told me to write more high school aus)  
> in which i finish up a fic that i've been planning for like nine months because they wanted me to write more high school aus lmao

Armin walked into his English class one Friday morning to find a small, triangularly-folded note sitting in stark contrast to his brown wooden desk. Curious, he picked it up and flipped it over, expecting to find something– he wasn’t sure what (maybe a name or something?)– on the back to cue him in as to its origin or purpose.

There was absolutely nothing.

For a moment, he considered tossing it, or asking his teacher, Ms. Nanaba, about it, as if she would know anything. But his curiosity got the best of him and he very carefully unfolded the note.

Before it was even all the way open, he saw numbers printed very neatly in the upper third of the paper; they had been cleverly hidden in the folds. It was not a code he was familiar with, so he finished unfolding it, and, finding nothing but numbers on the first side he saw, he flipped it over.

It was sheet music. Probably meaningless.

He flipped it over to the side with the numbers on it again.

_54 115 92.  16 20 23 98 32 80 / 1 92 7 22 / 22 8 / 9 49 60 / 42 54?_

They had no pattern whatsoever that he could see, and he was very good at looking into things and finding patterns in them. Perhaps the sheet music on the back had meaning after all…

He flipped it over a third time and tried to play the melody in his head. After a few seconds of struggling, its motifs began to become familiar as he got better at sight reading the rhythm and notes. Realization hit him like a pile of bricks: it was the Can-Can.

The same instant as the full piece began blasting in his head, words came as well: _This is the periodic table; noble gas’s stable; halogens and alkali–_

_They were atomic numbers._

Excited now, he checked his watch– he had three minutes until class officially started– and flipped the note over yet again.

54 – Iodine, I; that was easy.

115 – well, uh, if Copernicium was 111– Ununtrium, Flerovium, Ununpentium– _Livermorium_ , Lv.

92 – also easy: Uranium–

_I Lv U._

His thought process and excitement came to a screeching halt. Oh, _crap_ , was this a love confession note? It couldn’t have been for him– oh crap, oh crap– he was invading someone’s privacy–

He noticed another set of numbers up top.

 _To: 18 25 / 18 3 111_.

Well, if it wasn’t for him, then he could at least find who it was _really_ for and give it to them. He searched the table branded into his brain. Argon and Manganese, then Argon again, Lithium, and… Roentgenium. ArMn ArLiRg.

He assumed the Rg was meant to be an Rt (probably a memorization error on his own or the writer’s part, or simply out of desperation from the lack of diverse atomic symbols) because there was _no one_ in the entire school with a name even _remotely_ like that except for his own, so that meant–

The bell rang at that moment, but he could hardly hear it from the amount of disbelief that was crowding his head. Only when the lights turned off and the projector flickered to life did he quickly hide the note and begin to take his own notes on what was being projected.

But, between slides, he solved the rest of the code, ending up with:

_To: ArMn ArLiRg._

_I Lv U. SCaVEsGeRe HUNTi TiO FINd MoI?_

Or, as he scribbled beneath the cracked code (so that he couldn’t get an aneurysm from trying to read it over and over again when the words were butchered so horribly):

_I love you. Scavenger hunt to find me?_

There was no signature nor any other hints as to the writer’s identity, with the exception of perhaps their handwriting. He supposed that the whole anonymity thing was part of the mystery and scavenger hunt.

But how would he answer them? He knew he had to, otherwise he’d seem rude for ignoring them, and things _could_ turn awkward.

He supposed Ms. Nanaba had to know about and allow the note to make it to him; she tended to toss papers left behind on desks in the recycling bin between periods. If she, for _some reason_ , would allow the note to stay, then maybe she’d pass one back to the writer. Regardless of whether she agreed or not, it was his only guaranteed shot to getting the note to the right person.

Ah, but how would he word it? Just saying “okay” and then signing it seemed too strange, too uninterested. No, quite the contrary; if he didn’t figure this out, he felt as if it would eat away at his conscience for the rest of his life.

Well, it was a code involving the periodic table; he could make a similar code back at them.

He paused his train of thought on the response to scribble down some notes.

There was Potassium, K, and Oxygen, O. They could realistically come together to make K2O, dipotassium monoxide. But that was backwards.

Backwards. He could write the word form backwards. That should get his message across in a sufficiently cryptic manner.

He ripped out a corner of his notes, scribbled his reply on it, folded it in his own way, and tucked it away until the end of class.

The bell rang soon enough, and as his classmates escaped to their next class, Armin went against the current and up to Ms. Nanaba.

“Uhh, Ma’am?”

She looked up from her desk. “Yes, Armin?”

He pulled the notes out, suddenly feeling a little embarrassed. “I found this note for me from a different period– it seems like that anyway– and, uh, know you throw our most scraps left behind, I figured there must be a reason–”

“Why?” she finished for him, smiling a bit and calming him down.

He nodded and showed her his own tiny, folded note. “And if you could give a note with my response to them.”

She took it as she spoke. “I only helped her because she asked. That’s all. Now hurry along to your next class. You’ve got five minutes left.”

“Thank you!” he called as he left.

~***~

The next day, there was another note sitting plain as day on his desk. He slipped it into his pocket to solve later during lunch.

**Notes for the Chapter:**

> the roentgenium was legitimately my fault lmao. i was writing in class w/o access to a periodic table so i went off the table in my head and well i got the number right but not the symbol w hoopsie daisies. could've sworn it was Rt...  
> anyway this was going to be a oneshot, but then it got longer.... and longer....... and longer...........  
> so now i've divided it up by riddles and if you can guess the riddle or at least crack the code (b/c a fair number of the riddles themselves are based off my school's geography so that would be unfair) i will (maybe) write you a drabble of your desire. if i like the prompt. mmmmmMMMMmmm we'll see.  
> anyway that's all this time. peace out darlings, and have a greaaaaaaaaaat daaaaaaay~~


	2. Chapter 2

**Notes for the Chapter:**

> mm i love sending these snk kids to a dirt-poor school covered in gum wads modeled after my own.

“What’s that?” his friend Eren asked later during lunch.

Armin handed him the yet-unopened note. “It’s a puzzle.”

Eren opened and stared at it, clearly very confused. “Good luck, man. It’s just numbers.”

The blond boy laughed and took it back. “I know. They should be just atomic numbers arranged to make poorly spelled words. It’s not that hard.” He glanced at what the note had for him this time:

_68 / 9 77 16 / 17 92 / 3 99 / 49 / 74 85_

_Er first clue lies in wait_

_Er?_ Oh, it must have been for want of a Y for ‘yer’… even though Yttrium existed. At the very least, he could now at least joke that whoever liked him talked kind of like Hagrid…

_49 / 33 / 27 68 7 68 / 5 53 / 90 / 31 22._

_In a corner by the gate._

That _literally_ narrowed it down to about two general locations in the entire _school_. Well, this would be easier than he anticipated. He wasn’t sure whether the writer was making a pun on their possible sexuality by putting ‘BI’ in place of ‘by’, but he found it to be an entertaining thought.

_74 2 75 / 90 / 38 92 66 7 16 / 88 75 3 / 45 8 95,_

_Where the students rarely roam,_

…There were pretty much _always_ people by the two gates to the school, at least when he was there.

He hoped it wasn’t talking about a gate into the fourth dimension, because he didn’t have the funds to go into researching that quite yet. Or for the next few years.

_13 8 7 / 90 / 3 23 49 , 5 75 85 1 49 / 1 13_

_Along the living, breathing hall_

The _what_ now?

_3 99 / 18 / 45 8 76 / 90 85 / 53 / 6 13 / 67 25_

_Lies a room that I call home_

He really wished that the scientists could hurry up and discover more elements and give them single letter atomic symbols so that he wouldn’t have to suffer through all this bad spelling born out of desperation rather than stupidity.

And also, he had no idea what room _any_ student would call home on _their_ godforsaken, dirt-poor campus covered in gum wads. They either had to be pretty poor themselves (wouldn’t have surprised him; to get a poor school, you had to have poor residents funding the school), or that room had better be pretty damn homey.

_95 8 7 / 90 / 75 95 16 , 92 / 9 53 60 / 90 / 3 81 / 32 75 7 / 66 8 3._

_Among the reams, you find the little green dolly._

He handed the note, complete with the (hopefully) sensical translation of the code to Eren just as their friend Mikasa sat down with her own lunch. She too glanced over at the note with the riddle on it.

“It started out making sense, but then it fell into a downward spiral of nonsensical misspellings,” Armin lamented. “A ‘living, breathing hall’? I mean–” He was reduced to nothing but strange hand gestures and strangled noises; eventually, he flopped down onto their lunch table out of sheer confoundment.

“I’ve got nothing.” Mikasa shrugged as Eren handed back the note.

Armin looked it over again, rereading the riddle in its entirety, hoping that it would make more sense if read like that.

The only two locations by gates in the school would be the guard shack by the front of the school and the music and drama rooms in the outskirts of the back. Both were fairly populated in the mornings and afternoons, when everyone was entering or exiting the school. However, the back gate was the one with the hall that the least students traversed, since _no one_ liked going to the music or drama rooms because of how out of the way they were.

So, three options. The band room, the choir room, or the drama room. He _still_ had no idea what the ‘living, breathing’ line meant, but it seemed negligible for the moment.

Being a band student himself, he knew that many of his classmates considered the band room to be like a second home to them, hanging out there during lunch and pretty much living there as it seemed from time to time. From his few drama friends and even fewer choir friends, they seemed to think the same about their own respective rooms as well.

So, the line _“Lies a room that I call home”_ ruled out absolutely nothing.

But “reams” was a word for piles of sheet music bound together, which ruled out the drama classroom. That meant the little green dolly was…

_“Shrek,”_ he said aloud, probably sounding a lot more suspicious than he did epiphany-like.

“What?” his friends said in unison.

“The Shrek doll in the band room,” Armin explained. “You know, the one everyone likes to put their hats on? I’m pretty sure that’s where the next clue is.”

They looked blankly at him.

“...I explained someone left a crush note on my desk asking me if I wanted to go on a scavenger hunt to find them, right?”

_“What?”_ Eren cried.

“No,” Mikasa said right after.

“I thought it was just a random puzzle.”

Armin grinned sheepishly at them. “Well, uh–” for want of something better to do, he finger gunned them– “now you know.”

Eren peered curiously at him. “You’re really going on a wild goose chase to find someone like that?”

“Well, wouldn’t you?”

“Pff, no. Too much work.”

Armin began to inhale his lunch and pack up. “Well, you honestly have the brain capacity of a teaspoon sometimes. Some of us happen to have _curiosity_.” He stuffed the last of his food into his mouth and slung his backpack over his shoulder. “See ya later!”

~***~

He’d never been inside the band room for lunch before, aside from the few times he’d hung out with Eren and Mikasa in practice rooms because they had to practice or copy homework or whatever it was they needed to do in a soundproof, security-camera-free environment. Usually nothing _too_ illegal.

It was a lot less populated than he anticipated.

He wove his way passed the line of people waiting to use the lone microwave near the door, the only one students were allowed to use since the nurse stopped offering hers, passed the other line leading into the director’s office where store-bought goods were sold illegally as an infinitely-ongoing fundraiser, to the little table by the year-by-year panoramas of the marching band where the stuffed Shrek doll sat in all his Burger King crowned glory.

Feeling a little self-conscious, he stuck his head down the crown and felt around.

(He felt very awkward about it, and he silently vowed to never acknowledge that he ever did this, ever.)

There, wedged between the crown and the doll’s head was yet another note. He fished it out: it was folded into a triangle, just like the ones that had been on his desk had been. Not wanting to stand out in the open, he ducked into the nearest empty practice room to read it.

Muffled bass clarinet played in the background; though nobody outside the door could ever hear what went on inside the practice rooms, the walls between them were unfortunately thing. But he ignored it and read the side of the note that had English.

_In the laboratory, you are studying the first-order conversion of a reactant_ X _to products in a reaction vessel with a constant volume of 1.000 L. At 1:00 p.m., you start the reaction at 25℃ with 1.000 mol of_ X. _At 2:00 p.m., you find that 0.600 mol of_ X _remains, and you immediately increase the temperature of the reaction mixture to 35℃. At 3:00 p.m., you discover that 0.200 mol of_ X _is still present. You want to finish the reaction by 4:00 p.m. but need to continue it until only 0.010 mol of_ X _remains, so you decide to increase it once again. What is the minimum temperature required to convert all but 0.010 mol of_ X _to products by 4:00 p.m.?_

And then, just beneath that was:

_Now take your answer_  
_Negate by two and repeat_ _  
Until you’ve your code._

The problem itself was typed, unlike everything else he had so far received, all of which had been hand written. It was probably the sender’s old homework, or perhaps just a spare from their class. Alas, they must not have shared the same teacher, for he did not recognize the problem, but he got to work anyway.

Whoever was sending him these seemed to be really into poetry: the last handwritten bit on the bottom of the page had the syllable scheme of a haiku. He had to admit, he was a bit of a poetry freak as well, and _man_ did the alliteration in the last line please him.

_49℃._

He looked at his work and double checked everything. It had been a year since he had taken Chemistry (he had chosen not to take the AP course this year because he knew he would be bogged down by AP Lang) so he knew he was a little rusty. Satisfied, he was about to begin deciphering the haiku when the bell signalling the end of lunch rang.

With a sigh, he folded up the note, slung his backpack over his shoulder, and walked to class.

~***~

He snuck a peek at the back of the paper, where the true riddle lay, during history, hoping that perhaps it would make it more obvious as to what the haiku meant, for he had not the time to think about it at the moment.

_49 27 27  / 13 11 9 43 41 23 11 13  / 25 9 13 11  / 19 49 13 13_

_11 35 15 21 9 37 35  / 11 35 33 13  / 45 27 49 13 13_

_11 21  / 37 15 49 43 9 49 11 41 ._

_11 49 27 29  / 49 47 21 9 11  / -1 21 25 47 33 41 13_

_11 49 27 29  / 49 47 21 9 11  / 49 11 21 25 13_

_11 49 27 29  / 49 47 21 9 11  / 49 27 27  / 33 23  / 47 41 11 5 41 41 23 ._

_33 23  / 45 49 13 41  / 1 21 9  / 43 21 23 ’ 11  / 35 49 7 41  / 33 11_

_47 1  / 13 21 25 41  / 45 15 49 -1 1  / 25 49 37 33 45_

_11 35 33 13  / 45 27 49 13 13  / 33 13  / 49 27 13 21_

_49  / 45 27 9 47 ._

_25 49 49 ._

Oh. Oh dear. This one was quite long. He had no time to solve for it at the moment, not when dates called.

However, it did not escape him that all the numbers were odd.

**Notes for the Chapter:**

> easy code this time! i actually have no clue how to do that chem problem myself but i'm pretty sure it involves like three ice charts but i got it out of a college textbook's selected answers so i'm sure i'll learn it this upcoming year as i sell my soul to ap chem  
> also we actually do have a freaking shrek doll in our band room. i am not lying to you. allow me to embed a picture of it:  
>   
> that was shrek in my freshman year. last year it had a burger king crown on lol.  
> anyway the drabble offer still stands. (figure out the code and decode the riddle; solve if possible) take as long as you like coming up with whatever you like. my only limit is no porn and if possible stay within ships i'm comfortable writing (eremika, aruani, springles, yumikuri, jeanmarco, among a few other more minor ones)  
> .3. thank you all for your support!!!!! i didn't expect this much actually *nervously sweats* anyway have a greaat daaay~~


	3. Chapter 3

**Summary for the Chapter:**

> in which armin finds his third clue and looks at the big picture but not the details.

That evening, Armin collapsed with a sigh into his desk chair. It had been quite the day.

He lazily pulled the note out of his pocket, confident that he had cracked this one’s code. The answer to the Chem problem had been 49℃, which was the equivalent to A in the alphabet, and each letter following would be two less than the previous until Z, which was -1.

He sat up properly and unfolded the note, careful to turn his desk light on so that his grandfather wouldn’t chastise him later and say he was ruining his perfect eyesight.

He scribbled out the key on a piece of scratch paper and from there spent the next ten minutes meticulously decoding the numbers. When that was done, he leaned back in his chair and exhaled; he hadn’t even noticed he wasn’t breathing towards the end.

He picked up the riddle and read it aloud:

“ _All students must pass / Through this class / To graduate. / Talk about zombies / Talk about atoms / Talk about all in between. / In case you don’t have it / By some crazy magic / This class is also / A club. / Maa._ ”

He glanced up at the end. _“Maa?”_ he said, dumbfounded.

He read it over again, silently this time.

 _All students must pass through this class to graduate._ Well, that was an easy bit; it ruled out all the electives.

He supposed it wouldn’t be another English class, since that was where it had all started, and a scavenger hunt with two of the same items wasn’t much fun at all.

He also ruled out it being a PE class, since there was never much talking about anything except for that one unit of sex ed, let alone zombies, atoms, and anything in between. He shuddered, not wanting to think about the poorly given lectures of that month of his freshman year.

That left him with either math or science.

_Talk about zombies, talk about atoms, talk about all in between._

He stared off into space, chewing on his pinky, for a few moments as he gave those lines some thought. Math with Mr. Berner _could_ be wild sometimes, especially when Ms. Zoë dropped by during her prep periods to tell them all short but hilarious stories about Mr. Berner back when he was her student teacher, but for the most part, no math class he had ever taken since he had entered high school had ever really _talked_ about things other than, well, _math_.

His mind wandered off to the last time Ms. Zoë had popped into his Calc a/b class. Mr. Berner was off delivering some last minute paperwork or something, and she ended up rambling about how the reason Mr. Berner was prepared for everything down to the zombie apocalypse was because back when he was under her, he saw her accidentally explode an erlenmeyer flask because she thought it would be fun to show the kids what happens when you put three grams of pure Lithium in with distilled water.

But hey, at least no one got hurt because it was all in the fume hood.

Ah, Ms. Zoë and her qualifications to teach any subject she pleased. He remembered Mr. Berner telling them he was glad she mained in Chemistry because he wasn’t sure how he’d come to school at the end of every semester sober if she was the head of his department. He remembered it particularly because when they had been asked to exchange notes with the person sitting next to them, he had received a notebook full of zombies eating ropes made of integrals from the girl who sat next to him.

_Bang!_

He jumped, startled out of his flashback by the sound of his grandfather slamming the door shut, signalling his arrival.

 _“Armin,”_ his grandfather called, _“Did you finish your homework?”_

“Working on it!” Armin yelled back.

Shoving the riddle to the side, he dug his homework out of his backpack and began to work.

~***~

It was three in the morning. Armin was fast asleep in his bed, a feat astonishing for a junior loaded with ten million zillion AP classes.

His eyes suddenly snapped open.

_“Ms. Zoë coaches Academic Decathalon.”_

~***~

He arrived on campus early the next day. Lunch would be too long to wait; he had grown too invested in the scavenger hunt to simply wait half a day to only receive the next riddle. Plus, Ms. Zoë came early every day so he knew her class would be open.

He carefully opened the door leading into her class and peeked inside. At first it seemed empty, its lights strangely all on when–

“Good _morning_ , Armin! Oh, you always _were_ one of my favorite students!”

He screamed when she leapt in front of him, amused smile on her face, nearly falling onto his bum from shock. “Ms.– Ms.  Zoë! I di–”

“Oh, don’t worry about it, kiddo. You’re looking for something, no?”

Armin blinked, trying to process what just happened. “Uhh, yeah, actually.” He started to take the previous note out of his back pocket but Ms. Zoë would have none of it.

“Shht! You don’t need to show me. What, did you think I was oblivious to you kids’ runnings arounds and local gossip? She told me all about your little scavenger hunt after I asked her about unusual her margin doodles.” She paused for a second and broke into a grin. “It’s cute, I have to say. I came in early this morning so she could hide your next clue in here.”

She briefly checked her watch, but even then, Armin couldn’t get a word in for he had no words to say, he was so astonished.

“Oh! I have to go pick some stuff up from the office. I’ll be back in a jiff– oh, but don’t worry about being alone in the classroom. Billy’s watching.”

Flabbergasted, Armin could do nothing but watch her push past him and run down the hall, heels, lab coat, and all.

_Billy?_

He squeezed into her classroom, feeling as though he had to be sneaky because the room was devoid of any adult supervision and who _knew_ what he might accidentally blow up wandering through _Zoë’s_ classroom. Even if all the chemicals were locked up in a cupboard in the back with the only key belonging to Mr. Ackerman the janitor, he couldn’t know for sure.

He walked up to her desk, his quiet footsteps the only sound in the room. A white, fluffy stuffed alpaca in a lab coat and goggles smiled brightly at him with its eternal _:3_ face. The AcaDec mascot whom he just now remembered was named Billy. He stuck his hand into the little coat pocket, thinking perhaps it would be the stuffed animal that held the clue twice in a row. But alas, they were both empty.

As were Billy’s eyes as he stared, stared, stared at Armin, the only living thing in the room.

He quickly decided to move away; thinking about the alpaca gave him the creeps.

He wandered over to the far side of the room, where little student drawn safety posters hung in their little, plastic sleeves. One starred Deadpool and Spider-Man demonstrating how to care for lab-induced injuries; another, Mr. Ackerman and Ms. Zoë themselves arguing about proper chemical disposal.

A third one was a simple three-panel comic with a plain-looking boy doing a general lab. In the background, Billy the Alpaca watched. It zoomed in on Billy’s face, and in the last panel, he said, _“I’m watching you, Billy.”_

A connection of Billies. It wasn’t the strangest thing, in Armin’s opinion; this _was_ Zoë’s class.

He stared at the comic in total silence for a while. Something about it drew him.

Then, he noticed it wasn’t perfectly flush with the wall and that the opening was just a little bit wider than all the other little, plastic covers.

_Bingo._

He reached into the sleeve and pulled out yet another little, triangularly-folded paper and grinned.

~***~

_Lena had five different classes (English, math, science, history, and a foreign language) taught by five different teachers (Ral, Bozardo, Schultz, Jinn, and Ackerman). She had a different friend in every class: Hunter, Diana,  Constance, Mei, and Sean. Since Lena isn’t good at everything, her grades are all over the board with one of everything from an A to an F. Using the clues provided, deduce which period had what teacher teaching what class to Lena and her friend._

_1\. Lena’s best grade was her foreign language; her worst was history._   
_2\. Third or fifth period she had with either Diana or Sean._   
_3\. Second period was a grade above first; fifth was a grade above fourth, and third was a grade above fifth._   
_4\. Diana and Sean shared either math or science with Lena._   
_5\.  Schultz, Jinn, and Ackerman taught different grades during third and fifth._   
_6\. Schultz taught Mei and Lena, Constance was so stupid that constantly reteaching him the material accidentally made it her best subject, and her fourth period (which she did not share with Mei) wasn’t taught by Jinn._ _  
_ 7\. Sean’s help in their math class gave Lena one grade above her grade in Bozardo.

_Go to Lena’s second period and ask the teacher for their Hogwarts house._

~***~

It was then, as he was walking while reading the note and not paying attention to where he was going, when his friend Eren crashed into him from behind. He yelped, nearly dropping the little, folded-up paper, but Mikasa caught and stabilized him. They both stared at the note in his hands.

“Still doing that, Armin?” Eren asked.

“Well, it’s a different note from the first one, but yeah. Day two of this scavenger hunt.”

Mikasa gently took the note from him, read it for herself, and pursed her lips when she handed it back to him. “I recognize her handwriting.”

_“Her?”_

“We sat next to each other in English last year so I recognize it from having to grade her tests all the time.”

“Oh, yeah, huh. All the teachers that have mentioned them have been using she/her pronouns.”

“Armin, are you listening to me?”

He jumped, startled. He ran his hand through his hair. “Sorry. I just hadn’t been paying attention to some of the little things so it came as a shock when you told me it was a girl.”

“Well, what were you _hoping_ for?” Eren said incredulously. “A dude?”

Armin shrugged. “Hadn’t given it much thought. I figured I’d find out when I met them.”

Mikasa seemed to throw a subtle glare at someone behind the boys. “Well, I won’t ruin your fun and tell you who it is.”

“Yee.”

The bell rang for school to start, and the three friends parted ways: Mikasa to the locker rooms for her Badminton class, Eren to the science wing where he took AP Biology with Ms. Zoë, and Armin followed the marching band until he turned into the hall leading to his language class.

**Notes for the Chapter:**

> is acadec's mascot an alpaca only at my school?? is it every acadec's mascot??? i have no idea.  
> you know i love puzzlers like this. i forgot if this one was a level d or e. all i did was change around the labels for an existing puzzler lol. i solved it and wrote down the steps to how i for this fic bc honestly i wouldn't be able to remember my own logic and that is Not Good.  
> blowing up an erlenmeyer flask is yet another True Story and tbh like half of this is just weird stories that i've heard around my own school. except this riddle thing that's just fiction. the billy and deadpool comics are also True Stories and i'd provide pictures if i didn't absolutely know that the author of the billy comic hates having anything of theirs put on the internet and i have no idea which classmate drew the deadpool one. the last one mentioned was based off a headcanon someone on tumblr fed me and tbh the disregard for lab safety it had like scarred me.  
> i hope i'm doing this foreshadowing thing right. i mean you all know it's annie bc of the pairing thing but like _who she is_ in this universe.  
>  drabble offer is still open btw. i'd suggest making a table/chart for this one. there's no code to really crack this time bc i didn't want to encode the entire puzzler. hehe next chapter. next chapter's the kicker. that's about all! thanks for reading!!!!!!


	4. Chapter 4

He had just settled into his fourth period Calc class when the bell rang. Again. For much longer than the regular tardy bell.

The class, usually buzzing with chatter was stone silent. There had been no drills planned for the day, not that anyone had been informed of, anyway.

“Lockdown, folks,” Mr. Berner sighed, shutting and locking the door the second the bell stopped ringing. “Get under your desks, and I’ll turn off the light.”

So there Armin found himself, back to back with Annie, the girl who sat next to him, knees tucked in as they huddled in the dark beneath their conjoined desks. The classroom was abuzz with quiet chatter, its occupants excited, confused, and frightened all at once.

They were silent at first, but shockingly, Annie spoke up, quietly, with an air of apathy that just didn’t seem completely genuine.

“So. Have you been doing anything?”

Considering the circumstances,  Armin would have been more concerned if she were able to pull off perfect apathy, so he thought nothing of it. “Well, there’s this puzzle I’ve been working on,” he whispered to her, careful not to mention it was a scavenger hunt to find the girl who had confessed to him. “I got it this morning, but I haven’t had much time to work on it since, well, _class.”_

“What’s the puzzle?”

He wriggled around so that he could fish the slip of paper out of his pocket, unfolded it, and read it quietly to her.

A pause.

“Might I help?”

A pause from him as well. He’d solved all the other puzzles on his own and had taken a certain pride in doing so, too. But, no one else was even remotely interested in the hunt, so in a way that was the default.

“Sure,” he said, fumbling in the dark for a pen. “Let me just hand it to–”

“No,” she replied. “It’s all right. I’m good at puzzlers like these. What’s the first hint again?”

Armin quietly flipped over the paper, for he was already scribbling out the options on the back, and read it again best he could in the dark. _“Lena’s best grade was her foreign language; her worst was history.”_ He flipped it over again and was able to finish writing out the options before Annie spoke again.

“...Okay, we can’t use that yet. What about the next one?”

_“Third or fifth period she had with either Diana or Sean.”_

“How are you organizing these?”

“Uhh… five columns labeled _‘first’_ through _‘fifth’_ with a list of the friends’ names, the teachers names, the grades, and the subject names in the same order down every column.”

He felt her nod ever so slightly. “Scratch out Diana and Sean from the columns labeled first, second, and fourth.”

“Mmhm… _Second period was a grade above first; fifth was a grade above fourth, and third was a grade above fifth._ ” Armin gave it some thought, then scratched out the _F_ in the second column and the _A_ in first: second couldn’t be last if it was above another class, and vice versa for. He did the same for fifth and third.

“And because third period was a grade above fifth, but fifth was already a grade above fourth, third also could not have been the D,” he muttered.

“So that means second, third, and fifth could not have been history because they were not the worst grades,” Annie continued for him. Armin blinked, having not anticipated for her to do that for him. But he scratched history out of those columns anyway.

_“Diana and Sean shared either math or science with Lena.”_

“Not useful yet.”

 _“Schultz, Jinn, and Ackerman taught different grades during third and fifth.”_ He scratched them out of those columns before he even finished reading the line. _“Schultz taught Mei and Lena, Constance was so stupid that constantly reteaching him the material accidentally made it her best subject, and her fourth period (which she did not share with Mei) wasn’t taught by Jinn.”_

“Scratch Mei, Jinn, and Schultz out of fourth.

“Gotcha. _Sean’s help in their math class gave Lena one grade above her grade in Bozardo.”_

They continued on like this, whispering the logic between them between long stretches of silence as they used up all the obvious clues. After almost two hours had passed and the lockdown had still not been lifted, Armin broke the chain.

“What class were you supposed to have right about now?”

She sighed and leaned her head back so that it rested on his shoulder a bit. “Band. We’re practicing for the festival competition at Sina next month. It’s hell. The tenors are always rushing, the flutes are always dragging, and no one can ever hear the bassoon. Or anyone, really, when the trumpets are playing.” She shifted. “Our balance is horrendous, and we have to hear Ms. Nifa complain about it all the time.”

“Sounds… hectic.”

“It is. Oh, first and fourth could not have been the A’s because there were classes with better grades than they. Therefore, second period had to have been the A.”

He dutifully scratched out everything so that it complied with what Annie had told him. “I can’t believe we missed that,” he said.

“Mmhm.”

“So, what do you play? I played clarinet last year for concert band, but I didn’t want to do marching this year, so yeah.”

“Bass clarinet, but no one could ever hear me unless we played _Let it Go_ , like at the winter concert.”

They both heard her phone vibrate.

“Mina’s in Zoë. She says Ms. Zoë looked out the window and saw like ten million police officers swarming the baseball and football fields. Apparently, they’re catching some escaped convict, and we’re trending on our local Twitter.”

“Huh.” He wasn’t too concerned; the occasional updates kids gave to Mr. Berner for lack of official word from Principal Dok had told them that much, but it all seemed too surreal to really sink in. Besides, he was focused on the last few pieces of the puzzler falling into place.

“Aaaand they caught him. Bell to let us out should ring any minute now.”

And she was right.

It rang to let them out to a _very_ late lunch just as he scratched out the final cell.

~***~

_Second period: Jinn for foreign language. Lena shares it with Constance and got an A._

~***~

The Mr. Jinn at their school was not a foreign language teacher, but rather, a math teacher. His freshman math teacher, in fact, but that was beside the point.

Armin supposed the puzzler, while tailored to include real teachers’ names, couldn’t be completely accurate to the real life. And besides, all he was looking for in the puzzler was the teacher name. All other information discovered in the puzzler was irrelevant.

He caught Mr. Jinn just before he left his classroom for his own lunch break.

“Mr. Jinn!” Armin called, causing the man to pause as he locked the classroom door. He looked up and saw Armin, and a smile formed on his face.

“Armin,” he greeted. “Doing well in Calc?”

“Yeah, yeah. Just got out. Didn’t learn much today though.”

“I can imagine.”

“Mr. Jinn, what’s your Hogwarts house?”

He cracked a grin at his former student. “Right to the point, huh?” He began to unlock his room. “The real answer would be Hufflepuff, but the girl left me with a raven to give you.” He hurried back inside but came back in less than a minute, plopping the said stuffed raven into Armin’s hands. It had a scroll– _the riddle!_ – in its beak, which was held closed via a tiny, rubber hairband.

Armin pulled the tiny scroll out and tried to hand the bird back to his old teacher, but he shook his head. “That’s for you, kiddo.”

“O– okay.” He wasn’t sure what to do now, so he tucked the toy under his arm, waved goodbye to Mr. Jinn, and walked off to find Eren and Mikasa. As he did so, he took a look at what the scroll said.

 _Say hello to lisa,_ it said on the very front.

“I don’t know any Lisas,” he muttered as he unrolled it.

 _tiwpn tmicpn dehipn xhpn taswpn_  
_dgupn dcvtgapn pciwpn jhjpapn_ _  
_ dehipn gttiwpn djaslpn qpn

He looked at the scrambled mess of nonsense letters on the back.

“Oh, _come on!”_

**Notes for the Chapter:**

> i wonder if anyone caught that the names from the puzzler were just alterations of the canon characters'? mei is mikasa, hunter would be eren (bc you know, jaeger), sean is jean, diana is sasha (logic being sasha's a huntress who mains bow and arrow), and constance is just the full version of connie.  
> oh god this riddle. lisa, lisa, lisa. liiiisaaaaa. LISA. this one's the real kicker hehehe. also the last opportunity that you guys have to win le drabble.  
> (sorry to fullmetalguardian, who seems to be too busy to read this as it comes out even though it's for them D:)  
> man last year when we had a lockdown where a criminal hid on our baseball field, i was in band class, and the second the band teacher said "just do whatever as long as it's quiet. no one ever comes here bc it's so out of the way" this saxophone player started playing the first snk op and in my head i was like "I KNOW THAT THE SNK THEME GOES WITH EVERYTHING _BUT NOW IS NOT THE TIME_ "  
> anyway, i'll give you guys two weeks for this one. **o3o**. comments would be amazeballs 11/10 but it's really up to you if you wanna. have a greaaat daaayy~~


	5. Chapter 5

**Summary for the Chapter:**

> our journey is over, the music is ending, so take this riddle to find me at last

He showed it to his friends again when he found them. Mikasa said nothing, choosing instead to passively watch the riddle get solved, but the scribbles caught Eren’s attention, so he and Armin huddled over the piece of paper together.

“...Well, everything ends in a _-pn_. That’s probably just filler that we can get rid of,” Armin slowly said.

 _tiw tmic dehi xh tasw_  
_dgu dcvtga pciw jhjpa_ _  
dehi gttiw djasl q_

They stared at it for another minute.

“All right, but this _still_ doesn’t mean anything,” Eren said. “What’s on the other side, anyway?”

“ _‘Say hello to Lisa’_ ,” Armin replied. “But we don’t know any Lisas so maybe she’s overestimating my connections.”

“Maybe it’s some kind of code. Didn’t you say that the backs of all these notes have been relevant in some way or another?” Eren suggested as he flipped over the note anyway.

“Except for the last one, yeah. They provide the code… for which to solve… the riddle.” Armin stared at the scroll again.

Eren shrugged. “Well then, it’s probably important. And hey, this L isn’t even capitalized. Can’t be a person if it’s not a proper noun.”

Armin flipped it back to the gibberish side. Well, not _really_ gibberish. If he really tried, he supposed there could be a pattern to it. Perhaps it was one of those letter swap codes? But then?

Lisa.

Oh.

He turned it over yet again and underlined the L and A. “ _L is A_. It’s one of those letter swap codes where it starts with L as the letter A.”

“Nice,” Eren said as Armin started scribbling out the key on the empty part of the paper. “I guess that cracks that code.”

 _eth extn opst is eldh_  
_orf ongerl anth usual_ _  
opst reeth ouldw b_

They stared at the result.

“...Well, it’s better at least,” Eren said. They both gave it some thought for a moment, and then he said, “Maybe it’s like Pig Latin, where the end comes up to the front. What would _-pn_ come out to be in the letter code?”

Armin thought about it for a second. “ _-ay_ , like in Pig Latin. So if we rearrange it like that we get–”

 _The next stop is held_  
_For longer than usual_ _  
Stop three would B_

“...B?” he said, confused.

“Bees?” Eren asked.

 _“Bees?”_ Mikasa said, speaking for the first time since they had begun solving the riddle.

Armin handed her the cracked paper. “It just stops with the letter B.”

She read it over. “The first two lines sound like a fermata. Dunno what the last line would be.”

“Maybe she means the rooms where she planted the notes are ‘stops’,” Eren suggested. “Mr. Jinn was the third room, right?”

“Not counting Ms. Nanaba, yeah,” Armin answered. “But this just… doesn’t make any sense?”

They all huddled around the riddle, scrutinizing it and analyzing it from every angle they could think of.

“Hey, it’s a haik– oh, wait. The last line’s missing a syllable. Nevermind,” Armin sighed.

A few minutes passed and the friends stopped huddling, having memorized the not-quite-a-haiku.

“You still have that old invisible ink pen, right, Mikasa?” Eren suddenly blurted out.

She looked skeptically at him. “Yeah, it’s in my backpack, but why?”

“Worth a shot to find any hidden messages.”

“I think that’s a stretch,” Armin said, “But I guess it can’t hurt.”

So Mikasa took out her old invisible ink pen and shone the built in UV light on the side that said, _“Say hello to lisa”_ , and lo and behold! A faint fermata and a flat glowed beneath the blacklight.

“The next stop would _B♭_ ,” Armin said. He had no idea where it came from, just that it came to him. “Oh my god it’s that cheesy music pun _‘Without music, life would B♭’_ but in a different context with an incomplete haiku that we were supposed to complete. With the word flat. Which we have now done.”

“So now what?” Eren asked. “If the third stop is a fermata and the next one is a flat, then… ahhhh. You need to overlay the school map so that the fermata is where Mr. Jinn’s class is and wherever the flat falls would be where the next hint lies.”

“Yeah, that makes sense,” Armin replied.

“Hey Armin, I’m just curious, but why are you going through all this work to find this girl?” Mikasa asked. “I mean, I’m just saying. You _do_ have a lot to study without this kind of wild goose chase taking up your time and energy.”

“I dunno. I told her I would find her. Why do you ask?”

Mikasa’s normally stoic expression slipped into a frown for just a second, but she managed to keep her composure. “She’s not really someone I’m fond of.”

“Really? Who is it?” Eren asked.

Mikasa beckoned him over and whispered into his ear. He gave her a pointed look. “Oh, come on, Mikasa. She’s not that bad.”

Sensing an argument that might spoil the girl’s identity for Armin, he grabbed the note, stuffed it into the same pocket as the stuffed raven, and said, “There’s no such thing as an objectively good or bad person. Maybe Mikasa thinks she’s bad, but if she _likes_ me then I don’t think she’ll be a bad person to me.”

With that, the subject was dropped for the rest of their brief lunch.

~***~

It was half past one in the morning. Armin lay awake, staring at his empty ceiling, for his mind was too full to fall asleep.

But they were not full of thoughts on his schoolwork, or of all the AP homework he had half-assed that night. Nope; tonight he found his thoughts drawn to the girl who sent him on this scavenger hunt.

He had a hunch as to who she was based off little details scattered throughout his last two days that he had only now begun to string together. He could definitely see her doing this sort of thing; the girl he had in mind was the subtle type.

He’d never given her much thought before, but now that the possibility that she liked him loomed over the horizon, she seemed to be all he could think about.

He had long since found the room where he would find his next hint. He’d cracked code after code, riddle after riddle; he’d figured out so many puzzles _almost_ all on his own in the past two days, but he just couldn’t figure out how he felt about her.

He sighed into his pillow and tried to fall asleep once more.

~***~

“Mr. Smith?”

The extremely tall and eyebrowed man glanced up from his desk. “Armin. You’re at school early. Come in.”

Armin obeyed. “I don’t suppose this place would be flat?”

Mr. Smith’s eye suddenly had a dangerous gleam in it, a gleam that Armin would frankly have been afraid of had he not studied under him for the last few months. “Well that depends on what map you’re looking at. We’re on the second floor, after all.”

He pulled the note out from his pocket and cracked a smile. “This one, sir.”

“A job well done, Mr. Arlert. I have to say, the other teachers have been talking about this lately.”

“Have they?”

“They have indeed. It’s all Ms. Zoë would talk about during lunch yesterday. She thinks you guys are cute, and I daresay I find myself agreeing.” He reached into his desk drawer and pulled out a piece of paper folded in the same triangular style as almost all the other notes and handed it to Armin. “You’re almost there, lad. Give us a love story that’ll last the ages. Or at least a viral meme.”

Armin found his face flushed at Mr. Smith’s words. He knew the man tended to ship his students, supposedly because he had given up his own love for teaching, but this was just plain embarrassing. “Thanks, Mr. Smith. I’ll see you fifth period,” he squeaked and headed out the door.

~***~

 _Returning home, find the office_  
_Find the drawer that’s full of chopsticks_  
_Don’t be rude and buy our wares:_  
_Chocolates, chips, and cups of noodles_  
_Sweets and drinks among the doodles_  
_Bring one, bring none, but heed my rule:_  
_Should you bring some, I shall not show,_ _  
You’ll know me when you’re all alone._

“Chopsticks…” he muttered.  

That wasn’t the only thing about this particular note that had caught him off guard. There was no code to crack, just the riddle to solve, and by all accounts, it sounded like the band room. But he had already _been_ to the band room for this hunt, and even then he thought they didn’t have chopsticks.

He knew the nurse’s office had a drawer full of chopsticks because the nurse had a stash of cup noodles for whatever reason (probably in case a patient got hungry, but cup noodles…? Really?), but as far as he knew they didn’t sell anything.

He knew the second he read the last three lines, he knew this was his final stop. He was going to see if his hunch was correct. But what he couldn’t really get was _why make the last note so simple?_

They really _had_ been getting progressively harder, so to be left with only a riddle to solve was a bit of a disappointment. But he supposed it wasn’t easy coming up with all these codes to crack and riddles to solve…

He read it over again. He checked his watch. He had just enough time to run down to the nurse’s office before the bell rang for classes to start, so if he was going to start somewhere, might as well be there.

~***~

She had not been in the nurse’s office. He ran to class soon after he found out and left the riddle to stew in the back of his mind as he went through his first four classes of the day regularly. Perhaps it was the band room after all.

He decided to skip lunch with Eren and Mikasa for the day, he knew they wouldn’t mind, and made a beeline for the band room.

It was less crowded today than it had been the first day he had come in and retrieved the note from the Shrek doll, but perhaps that was because lunch had just begun. His hunch was nowhere in sight, but he suspected she was in a practice room.

He recognized Jean, a trumpet player in the previous year’s concert band, as he walked out of Ms. Nifa’s office with an unopened cup of noodles and– _gasp_ – a pair of cheap chopsticks. That confirmed it: he was in the right place.

He walked into the black market office and found it empty save a girl he knew named Sasha, who greeted him brightly.

“Haven’t seen you in here since last year, Armin! You’re not thinking of transferring back into band? We could use someone as good as you. Just the other day I was passing by during concert period, and I heard the most _awful_ squeak.”

He shook his head. “Just back for a visit. I’m looking for someone– _don’t_ **_tell_** _me_ – but I’ll have a cup of ramen.”

“That’ll be a dollar, then.”

He walked back out with his goods and surveyed the room. There was definitely a line for hot water and the microwave, so he decided cooking his noodles could wait. Instead, he turned to the practice rooms.

The one where he had read the first riddle was taken, but the next one’s light was off. Knowing her, she was probably just trying to keep the mystery up for as long as she could, if she had a regular practice room at all.

He opened the door up a crack and slipped inside, not turning on the light at first so that he might surprise her rather than vice versa, but before he could flip the switch, the door closed behind him, and just as he did manage to turn on the light, hands slipped over his eyes.

“I guess you found me,” a dryly familiar and _completely_ expected voice said. “Nice job on that; I worked really hard on those riddles. But it’s not over yet: you still have to guess who I am.”

“Annie, please.”

Her hands came away from his eyes, and he had to blink a few times to be able to see properly again.

“So you _knew_ I liked you.”

“Not you for _sure,_ but I’ve had a hunch.”

He turned to face her, and they stared at each other for a good, long moment. Her face was bright red, and as the time passed, he found his was probably getting there, too. He found he had no words to say to her despite having spent hours the night before thinking about what he would say if he were right. Nor did Annie say anything, and Armin suspected it was for the same reasons as his own.

Armin swore he could feel time crawling by on his skin. Crap, he was panicking; _crap_ , he had no idea what to say, and _crap_ , he wasn’t giving Mr. Smith either the love story that would last the ages _or_ the viral meme.

“...I half expected you not to come,” she said, breaking the silence at last.

He blinked. “But why wouldn’t I?”

She broke his gaze and shrugged, looking instead at the out-of-tune piano. “I figured you’d lose interest in the riddles after a while and think you were wasting your time with it all and just… stop.”

“Well, lucky for you, I like riddles.”

She laughed. “I think this confession is proof enough of that.” It was strange hearing her voice so devoid of apathy, but also beautiful.

“Riddle me this, then:

“Will you go on a date with me?”

**Notes for the Chapter:**

> i know i said i'd wait two weeks but i'm not patient at all  
> my original plan for this was to post it for aruani week but then i got impatient. i've got a thing written for then now anyway.  
> jean....... is a trumpet player. i'm never letting that headcanon go ever. i know too many trumpet players. jean would totally be one of them along with eren. they'd have the stupidest trumpet adventures including but not limited to making farting noises all the time. i have this whole school band au planned out w/my friend and i don't think i'd write it all as one coherent story but man. trumpets eren and jean.  
> the "love story to last the ages or at least a viral meme" line is actually taken from a book series i read over the summer called unwind and this little old lady said it when the two mains met each other again after like six months or so apart and honestly best line old lady. best line.  
> i considered having an epilogue date for them but i promised i'd get a 5 on the ap chem test come may and ap chem is notoriously the hardest ap test to pass. IT'S FOR HONOR.  
> anyway thank you fullmetalguardian again for wanting me to write more high school aus, thank you mesq for your regular comments. thanks to everyone who left kudos!!! y'all are the best!!! and with that, i leave you with a few lines of.... 
> 
> **bonus ending**
> 
> She laughed again. “That’s not a riddle.”  
> “Well, why not?”  
> “Riddles are hard; they’re supposed to make you think.”  
> “Mm, well then, what’s your answer?”  
>  _“Yes.”_


End file.
